Packages for 2 or more semiconductor die are well known. Thus it is desirable to provide packages with two or more interconnected MOSFETs as for a buck converter circuit or a general half bridge circuit, or to provide one or more MOSFETs, or IGBTs or the like with an IC controller chip in the same package.
The cooling of such packages is a critical problem. It would be desirable to cool the die in such packages from both surfaces, while also permitting economical manufacture and assembly of such packages.